package com.killLog.service.impl;

import com.killLog.context.BaseContext;
import com.killLog.dto.ShoppingCartDTO;
import com.killLog.entity.Dish;
import com.killLog.entity.Setmeal;
import com.killLog.entity.ShoppingCart;
import com.killLog.mapper.DishMapper;
import com.killLog.mapper.SetmealMapper;
import com.killLog.mapper.ShoppingCartMapper;
import com.killLog.service.ShoppingCartService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.time.LocalDateTime;
import java.util.List;

@Service
@Slf4j
public class ShoppingCartServiceImpl implements ShoppingCartService {
    @Autowired
    private ShoppingCartMapper shoppingCartMapper;
    @Autowired
    private DishMapper dishMapper;
    @Autowired
    private SetmealMapper setmealMapper;

    /**
     * 添加购物车
     * @param shoppingCartDTO
     */
    public void addSoppingCart(ShoppingCartDTO shoppingCartDTO) {
        //判断当前加入购物车的商品是否已经存在了
        ShoppingCart shoppingCart = new ShoppingCart();
        BeanUtils.copyProperties(shoppingCartDTO,shoppingCart);
        Long userId = BaseContext.getCurrentId();//获取TreadLocal里面的共享空间的用户id
        shoppingCart.setUserId(userId);
        List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);

        //如果已经存在了，只需要将数量加一
        if (list!=null && list.size()>0){
            ShoppingCart cart = list.get(0);//取出里面的第一条数据
            cart.setNumber(cart.getNumber()+1);
            shoppingCartMapper.updateNumberById(cart);
        }else {//如果不存在，就需要插入一条购物车数据
            //判断本次添加到购物车的是菜品还是套餐
            Long dishId = shoppingCartDTO.getDishId();
            if (dishId!=null){
                //本次添加到购物车的是菜品
                Dish dish = dishMapper.getById(dishId);
                shoppingCart.setName(dish.getName());
                shoppingCart.setImage(dish.getImage());
                shoppingCart.setAmount(dish.getPrice());
            }else {
                //本次添加到购物车的是套餐
                Long setmealId = shoppingCartDTO.getSetmealId();
                Setmeal setmeal = setmealMapper.getById(setmealId);
                shoppingCart.setName(setmeal.getName());
                shoppingCart.setImage(setmeal.getImage());
                shoppingCart.setAmount(setmeal.getPrice());
            }
            shoppingCart.setNumber(1);
            shoppingCart.setCreateTime(LocalDateTime.now());

            shoppingCartMapper.insert(shoppingCart);
        }
    }

    /**
     * 查看购物车
     * @return
     */
    public List<ShoppingCart> showShoppingCart() {
        //获取到当前微信用户的id
        Long userId = BaseContext.getCurrentId();
        ShoppingCart shoppingCart = ShoppingCart.builder()
                .userId(userId)
                .build();
        List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);
        return list;
    }

    /**
     * 清空购物车
     */
    public void cleanShoppingCart() {
        //获取到当前微信用户的id
        Long userId = BaseContext.getCurrentId();
        //调用持久层删除
        shoppingCartMapper.deleteByUserId(userId);
    }


    /**
     * 删除购物车
     * @param shoppingCartDTO
     */
    @Override
    public void subtract(ShoppingCartDTO shoppingCartDTO) {
        //获取当前微信用户id
        Long userId = BaseContext.getCurrentId();
        //根据dishId或者setmealId查询购物车
        Long dishId = shoppingCartDTO.getDishId();
        ShoppingCart shoppingCart = new ShoppingCart();
        BeanUtils.copyProperties(shoppingCartDTO,shoppingCart);
        shoppingCart.setUserId(userId);

        if(shoppingCart.getDishId() != null){
            //当前商品为菜品
            ShoppingCart cart = shoppingCartMapper.getByUserIdAndDishId(shoppingCart);
            //如果购物车中商品数量大于1 则对应商品数量减少1
            cart.setNumber(cart.getNumber() - 1);

            if(cart.getNumber() == 0){
                //如果减少后购物车中商品数量等于0 则删除购物车中的商品数据
                shoppingCartMapper.deleteByShoppingId(cart.getId());
            }else {
                //如果减少后购物车中商品数量>=1 则跟新购物车中的商品数据
                shoppingCartMapper.updateNumberById(cart);
            }
        }else {
            //当前商品为套餐
            ShoppingCart cart = shoppingCartMapper.getByUserIdAndSetmealId(shoppingCart);
            //如果购物车中商品数量大于1 则对应商品数量减少1
            cart.setNumber(cart.getNumber() - 1);

            if(cart.getNumber() == 0){
                //如果减少后购物车中商品数量等于0 则删除购物车中的商品数据
                shoppingCartMapper.deleteByShoppingId(cart.getId());
            }else {
                //如果减少后购物车中商品数量>=1 则跟新购物车中的商品数据
                shoppingCartMapper.updateNumberById(cart);
            }
        }
    }
}
